\x89\x50\x4E\x47\x0D\x0A\x1A\x0A
 PNG

\x89\x50\x4E\x47\x0D\x0A\x1A\x0A
## Here is an example for quoted emails (under e.g. mutt).

syntax mutt

# Quoted lines.
color green "^>.*"

# Signatures, even quoted ones.
color yellow start="^>* ?-- $" end="^>* ?$"